1. Field of the Invention
The present invention generally relates to an AC adapter such as an AC adapter including a first circuit board on which an electronic device is mounted, a second circuit board electrically connected to the first circuit board, and a connector provided to the second circuit board and electrically connected to the second circuit board.
2. Description of the Related Art
As one example of an AC adapter for supplying electric power to an electronic device (e.g., portable electronic device), there is an AC adapter having a connector for connecting an AC cord. With this kind of AC adapter, the circuit board of the AC adapter or the electronic device mounted on the circuit board may be damaged by stress caused by repetitive inserting and pulling of the AC cord.
In order to prevent damage of the circuit board and the electronic device, an AC adapter of a related art example includes a circuit board that is divided into a first circuit board on which an electronic device is mounted and a second circuit board to which a connector is connected (see, for example, FIGS. 8 and 9).
FIG. 8 is a plan enlarged view of a connection part that connects first and second circuit boards of an AC adapter 200 according to a related art example. FIG. 9 is a schematic diagram of the configuration illustrated in FIG. 8 in a case where the configuration is viewed from letter J of FIG. 8. For the sake of convenience, an insulation case of the AC adapter 200 is omitted from FIGS. 8 and 9.
With reference to FIGS. 8 and 9, the AC adapter 200 includes a first circuit board 201, an electronic device 202, a second circuit board 204, a connector 205, wires 207, 208, and an insulation case (not illustrated).
The first circuit board 201 is a substrate having a greater area than that of the second circuit board 204. The first circuit board 201 includes a planar substrate body 211 and a wiring pattern 212 formed on a first surface 211A of the substrate body 211.
The electronic device 202 is mounted on the first surface 211A of the substrate body 211 and electrically connected to the wiring pattern 212. The electronic device may be, for example, a capacitor, a transformer, or a switching device.
The second circuit board 204 includes a planar substrate body 215 and wiring patterns 217, 218 formed on a first surface 215A of the substrate body 215.
The connector 205 is mounted on a second surface 215B of the substrate body 215. The connector 205 is electrically connected to the wiring patterns 217, 218. The connector 205 has a plug connection surface 205A provided on the side to which a plug (not illustrated) of an AC cord is connected. The plug (not illustrated) of the AC cord is repetitively inserted into and pulled out from the connector 205.
The wirings 207, 208 are formed of wires covered with an insulation material. Both ends of the wires of the wirings 207, 208 are exposed from the insulation material. A first end part of the wire of the wiring 207 penetrates through the first circuit board 201 and is electrically connected to the wiring pattern 212. Further, the other end part of the wire of the wiring 207 penetrates through the second circuit board 204 and is electrically connected to the wiring pattern 218.
A first end part of the wire of the wiring 208 penetrates through the first circuit board 201 and is electrically connected to the wiring pattern 212. Further, a second end part of the wire of the wiring 208 penetrates through the second circuit board 204 and is electrically connected to the wiring pattern 217.
The insulation case (not illustrated) is a case for installing the first circuit board 201, the electronic device 202, the second circuit board 202, the connector 205, and the wirings 207, 208 therein. The first circuit board 201, the electronic device 202, the second circuit board 202, the connector 205, and the wirings 207, 208 are stored in a state that the plug connection surface 205A of the connector 205 is exposed (see, for example, Japanese Laid-Open Patent Application No. 2006-12618).
With the AC adapter 200 according to the related art example, there is a problem that the cost of the AC adapter 200 increases because the first and second circuit boards 201, 204 are connected by using expensive wirings 207, 208 that have an insulation material covering the wires of the wirings 207, 208.
Further, in connecting the wirings 207, 208 to the first and second circuit boards 201, 204, a step of removing the insulating material at the first and second end parts of the wirings 207, 208 is required for enabling wires of the wirings 207, 208 become exposed at the first and second end parts of the wirings 207, 208.